{"id":3187,"date":"2025-09-29T15:29:43","date_gmt":"2025-09-29T15:29:43","guid":{"rendered":"https:\/\/xceed.com\/?p=3187"},"modified":"2026-02-16T19:26:28","modified_gmt":"2026-02-16T19:26:28","slug":"quoi-de-neuf-dans-net-9-guide-complet-de-la-version","status":"publish","type":"post","link":"https:\/\/xceed.com\/fr\/blog\/all\/whats-new-in-net-9-complete-release-guide\/","title":{"rendered":"Quoi de neuf dans .NET 9 : Guide complet de la version"},"content":{"rendered":"<div data-elementor-type=\"wp-post\" data-elementor-id=\"3187\" class=\"elementor elementor-3187\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-2991d137 e-flex e-con-boxed e-con e-parent\" data-id=\"2991d137\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-4d33950 elementor-widget elementor-widget-text-editor\" data-id=\"4d33950\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Le guide de publication de .NET 9 est l\u00e0 pour vous aider \u00e0 naviguer dans les changements majeurs du d\u00e9veloppement .NET moderne. Des avanc\u00e9es majeures en mati\u00e8re de performances et un d\u00e9veloppement cloud unifi\u00e9 aux puissants diagnostics et mises \u00e0 niveau de s\u00e9curit\u00e9, .NET 9 transforme la fa\u00e7on dont les \u00e9quipes construisent, d\u00e9ploient et mettent \u00e0 l'\u00e9chelle. Dans ce guide, d\u00e9couvrez les fonctionnalit\u00e9s les plus percutantes et voyez comment les composants Xceed rendent votre migration et votre modernisation transparentes.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-248f63f elementor-widget elementor-widget-heading\" data-id=\"248f63f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h1 class=\"elementor-heading-title elementor-size-default\"><h2 class=\"wp-block-heading\" style=\"--tw-scale-x: 1;--tw-scale-y: 1;--tw-pan-x:;--tw-pan-y:;--tw-pinch-zoom:;--tw-scroll-snap-strictness: proximity;--tw-gradient-from-position:;--tw-gradient-via-position:;--tw-gradient-to-position:;--tw-ordinal:;--tw-slashed-zero:;--tw-numeric-figure:;--tw-numeric-spacing:;--tw-numeric-fraction:;--tw-ring-inset:;--tw-ring-offset-width: 0px;--tw-ring-offset-color: #fff;--tw-ring-offset-shadow: 0 0 #0000;--tw-ring-shadow: 0 0 #0000;--tw-shadow: 0 0 #0000;--tw-shadow-colored: 0 0 #0000;--tw-blur:;--tw-brightness:;--tw-contrast:;--tw-grayscale:;--tw-hue-rotate:;--tw-invert:;--tw-saturate:;--tw-sepia:;--tw-drop-shadow:;--tw-backdrop-blur:;--tw-backdrop-brightness:;--tw-backdrop-contrast:;--tw-backdrop-grayscale:;--tw-backdrop-hue-rotate:;--tw-backdrop-invert:;--tw-backdrop-opacity:;--tw-backdrop-saturate:;--tw-backdrop-sepia:;--tw-contain-size:;--tw-contain-layout:;--tw-contain-paint:;--tw-contain-style:\">Pourquoi .NET 9 est important pour les d\u00e9veloppeurs<\/h2><div><br><\/div><p style=\"--tw-scale-x: 1;--tw-scale-y: 1;--tw-pan-x:;--tw-pan-y:;--tw-pinch-zoom:;--tw-scroll-snap-strictness: proximity;--tw-gradient-from-position:;--tw-gradient-via-position:;--tw-gradient-to-position:;--tw-ordinal:;--tw-slashed-zero:;--tw-numeric-figure:;--tw-numeric-spacing:;--tw-numeric-fraction:;--tw-ring-inset:;--tw-ring-offset-width: 0px;--tw-ring-offset-color: #fff;--tw-ring-offset-shadow: 0 0 #0000;--tw-ring-shadow: 0 0 #0000;--tw-shadow: 0 0 #0000;--tw-shadow-colored: 0 0 #0000;--tw-blur:;--tw-brightness:;--tw-contrast:;--tw-grayscale:;--tw-hue-rotate:;--tw-invert:;--tw-saturate:;--tw-sepia:;--tw-drop-shadow:;--tw-backdrop-blur:;--tw-backdrop-brightness:;--tw-backdrop-contrast:;--tw-backdrop-grayscale:;--tw-backdrop-hue-rotate:;--tw-backdrop-invert:;--tw-backdrop-opacity:;--tw-backdrop-saturate:;--tw-backdrop-sepia:;--tw-contain-size:;--tw-contain-layout:;--tw-contain-paint:;--tw-contain-style:\"><\/p><ul class=\"wp-block-list\" style=\"--tw-scale-x: 1;--tw-scale-y: 1;--tw-pan-x:;--tw-pan-y:;--tw-pinch-zoom:;--tw-scroll-snap-strictness: proximity;--tw-gradient-from-position:;--tw-gradient-via-position:;--tw-gradient-to-position:;--tw-ordinal:;--tw-slashed-zero:;--tw-numeric-figure:;--tw-numeric-spacing:;--tw-numeric-fraction:;--tw-ring-inset:;--tw-ring-offset-width: 0px;--tw-ring-offset-color: #fff;--tw-ring-offset-shadow: 0 0 #0000;--tw-ring-shadow: 0 0 #0000;--tw-shadow: 0 0 #0000;--tw-shadow-colored: 0 0 #0000;--tw-blur:;--tw-brightness:;--tw-contrast:;--tw-grayscale:;--tw-hue-rotate:;--tw-invert:;--tw-saturate:;--tw-sepia:;--tw-drop-shadow:;--tw-backdrop-blur:;--tw-backdrop-brightness:;--tw-backdrop-contrast:;--tw-backdrop-grayscale:;--tw-backdrop-hue-rotate:;--tw-backdrop-invert:;--tw-backdrop-opacity:;--tw-backdrop-saturate:;--tw-backdrop-sepia:;--tw-contain-size:;--tw-contain-layout:;--tw-contain-paint:;--tw-contain-style:\"><p style=\"--tw-scale-x: 1;--tw-scale-y: 1;--tw-pan-x:;--tw-pan-y:;--tw-pinch-zoom:;--tw-scroll-snap-strictness: proximity;--tw-gradient-from-position:;--tw-gradient-via-position:;--tw-gradient-to-position:;--tw-ordinal:;--tw-slashed-zero:;--tw-numeric-figure:;--tw-numeric-spacing:;--tw-numeric-fraction:;--tw-ring-inset:;--tw-ring-offset-width: 0px;--tw-ring-offset-color: #fff;--tw-ring-offset-shadow: 0 0 #0000;--tw-ring-shadow: 0 0 #0000;--tw-shadow: 0 0 #0000;--tw-shadow-colored: 0 0 #0000;--tw-blur:;--tw-brightness:;--tw-contrast:;--tw-grayscale:;--tw-hue-rotate:;--tw-invert:;--tw-saturate:;--tw-sepia:;--tw-drop-shadow:;--tw-backdrop-blur:;--tw-backdrop-brightness:;--tw-backdrop-contrast:;--tw-backdrop-grayscale:;--tw-backdrop-hue-rotate:;--tw-backdrop-invert:;--tw-backdrop-opacity:;--tw-backdrop-saturate:;--tw-backdrop-sepia:;--tw-contain-size:;--tw-contain-layout:;--tw-contain-paint:;--tw-contain-style:;font-size: medium;font-weight: 400\"><\/p><\/ul><\/h1>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-20c54cd9 elementor-widget elementor-widget-text-editor\" data-id=\"20c54cd9\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>Saut de performance :<\/strong><br \/>Les optimisations de CoreCLR, un JIT plus intelligent et l'E\/S asynchrones rendent vos applications plus rapides et plus l\u00e9g\u00e8res, d\u00e8s leur sortie de la bo\u00eete.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>D\u00e9veloppement unifi\u00e9 :<\/strong><br \/>Les plateformes web, de bureau et cloud sont plus convergentes que jamais : une seule base de code, plus de port\u00e9e.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>Mises \u00e0 niveau des outils :<\/strong><br \/>Visual Studio 2025 et les am\u00e9liorations de la CLI rationalisent toutes les \u00e9tapes du cycle de vie du d\u00e9veloppement.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><\/p>\n<p><!-- \/wp:list --><!-- wp:heading {\"level\":3} --><\/p>\n<h3 class=\"wp-block-heading\">Caract\u00e9ristiques cl\u00e9s et am\u00e9liorations<\/h3>\n<p><!-- \/wp:heading --><!-- wp:list --><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\"><!-- wp:list-item --><\/ul>\n<\/li>\n<\/ul>\n<p>\u00a0<\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>Rechargement \u00e0 chaud pour Blazor et WPF :<\/strong><br \/>Mettez \u00e0 jour les interfaces utilisateur instantan\u00e9ment sans reconstructions compl\u00e8tes. Une it\u00e9ration plus rapide = moins de friction, plus de productivit\u00e9.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>Virtualisation asynchrone :<\/strong><br \/>Support am\u00e9lior\u00e9 pour les grands ensembles de donn\u00e9es \u2014 id\u00e9al pour les tableaux de bord en temps r\u00e9el et les sc\u00e9narios Xceed DataGrid.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>APIs Cloud-Native :<\/strong><br \/>Int\u00e9grations simplifi\u00e9es avec Azure, AWS et GCP. D\u00e9veloppez et d\u00e9ployez des applications .NET sans serveur ou conteneuris\u00e9es avec une friction minimale.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>Diagnostic am\u00e9lior\u00e9 :<\/strong><br \/>La g\u00e9n\u00e9ration de rapports de performance int\u00e9gr\u00e9e, l'analyse des threads et l'interface utilisateur de diagnostic vous aident \u00e0 d\u00e9tecter les probl\u00e8mes de performance \u00e0 un stade pr\u00e9coce.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>Durcissement de la s\u00e9curit\u00e9 :<\/strong><br \/>Nouvelles biblioth\u00e8ques cryptographiques, HTTPS par d\u00e9faut et sandboxing \u2014 particuli\u00e8rement critiques pour les projets fintech, de sant\u00e9 et gouvernementaux.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --><\/p>\n<p><!-- \/wp:list --><!-- wp:heading {\"level\":3} --><\/p>\n<h3 class=\"wp-block-heading\">Comment .NET 9 Acc\u00e9l\u00e8re la Valeur des Composants Xceed<\/h3>\n<p><!-- \/wp:heading --><!-- wp:list --><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\"><!-- wp:list-item --><\/ul>\n<\/li>\n<\/ul>\n<p>\u00a0<\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>WPF Toolkit et DataGrid\u00a0:<\/strong><br \/>La virtualisation de donn\u00e9es asynchrone et les nouvelles API de th\u00e8mes signifient une exp\u00e9rience utilisateur plus fluide et une int\u00e9gration plus facile avec les backends modernes.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>Zip pour .NET et Zip en temps r\u00e9el :<\/strong><br \/>Les primitives d'E\/S asynchrones fournissent une compression plus rapide et plus fiable pour les charges de travail \u00e0 haut d\u00e9bit.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ul class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ul class=\"wp-block-list\">\n<li><strong>Th\u00e8mes professionnels :<\/strong><br \/>Les crochets de style XAML mis \u00e0 jour et les am\u00e9liorations d'accessibilit\u00e9 vous aident \u00e0 livrer des applications visuellement soign\u00e9es et conformes.<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!-- \/wp:list-item --><\/p>\n<p><!-- \/wp:list --><!-- wp:heading {\"level\":3} --><\/p>\n<h3 class=\"wp-block-heading\">Migration et meilleures pratiques<\/h3>\n<p><!-- \/wp:heading --><!-- wp:list {\"ordered\":true} --><\/p>\n<ol class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ol class=\"wp-block-list\"><!-- wp:list-item --><\/ol>\n<\/li>\n<\/ol>\n<p>\u00a0<\/p>\n<ol class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ol class=\"wp-block-list\">\n<li><strong>Audit des d\u00e9pendances :<\/strong><br \/>Mettre \u00e0 jour les paquets NuGet et v\u00e9rifier la compatibilit\u00e9 .NET 9 pour toutes les biblioth\u00e8ques, en particulier celles li\u00e9es \u00e0 l'interface utilisateur et \u00e0 la gestion des fichiers.<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ol class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ol class=\"wp-block-list\">\n<li><strong>Utiliser le rechargement \u00e0 chaud :<\/strong><br \/>Int\u00e9grez le rechargement \u00e0 chaud dans votre flux de travail pour une it\u00e9ration rapide de l'interface utilisateur, cela change la donne pour la productivit\u00e9 de l'int\u00e9gration et des essais.<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ol class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ol class=\"wp-block-list\">\n<li><strong>Profil t\u00f4t :<\/strong><br \/>Utilisez les nouveaux outils de diagnostic pour \u00e9tablir des performances de r\u00e9f\u00e9rence et d\u00e9tecter les r\u00e9gressions avant qu'elles n'atteignent la production.<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n<p><!-- \/wp:list-item --><!-- wp:list-item --><\/p>\n<ol class=\"wp-block-list\">\n<li style=\"list-style-type: none;\">\n<ol class=\"wp-block-list\">\n<li><strong>Restez en s\u00e9curit\u00e9<\/strong><br \/>Activer les nouvelles configurations de s\u00e9curit\u00e9 par d\u00e9faut et examiner les modifications apport\u00e9es aux API pour les projets critiques en mati\u00e8re de conformit\u00e9.<\/li>\n<\/ol>\n<\/li>\n<\/ol>\n<p><!-- \/wp:list-item --><\/p>\n<p><!-- \/wp:list --><!-- wp:heading {\"level\":3} --><\/p>\n<h3 class=\"wp-block-heading\"><strong>Pr\u00eat \u00e0 construire avec .NET 9 ?<\/strong><\/h3>\n<p><!-- \/wp:heading --><!-- wp:paragraph --><\/p>\n<p>Les composants .NET de Xceed sont enti\u00e8rement compatibles et optimis\u00e9s pour .NET 9.<\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph --><\/p>\n<p><mark class=\"has-inline-color has-primary-color\" style=\"background-color: rgba(0, 0, 0, 0);\"><strong>Commencez votre essai gratuit de 45 jours :<\/strong><br \/><\/mark><a href=\"https:\/\/xceed.com\/fr\/proces\/\">https:\/\/xceed.com\/trial\/<\/a><\/p>\n<p><!-- \/wp:paragraph --><!-- wp:heading --><\/p>\n<h2 class=\"wp-block-heading\">FAQ : Sortie de .NET 9 et compatibilit\u00e9 avec Xceed<\/h2>\n<p><!-- \/wp:heading --><!-- wp:paragraph --><\/p>\n<p><mark class=\"has-inline-color has-primary-color\" style=\"background-color: rgba(0, 0, 0, 0);\"><strong>Les composants Xceed sont-ils pr\u00eats pour .NET 9 ?<\/strong><br \/><\/mark>Oui. Toutes les biblioth\u00e8ques d'interface utilisateur et de fichiers Xceed majeures sont test\u00e9es et optimis\u00e9es pour .NET 9. Contactez-nous si vous avez besoin de conseils pour la migration.<\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph --><\/p>\n<p><mark class=\"has-inline-color has-primary-color\" style=\"background-color: rgba(0, 0, 0, 0);\"><strong>Mes projets WPF existants seront-ils mis \u00e0 niveau en douceur ?<\/strong><br \/><\/mark>A: Dans la plupart des cas, oui, surtout avec les d\u00e9pendances mises \u00e0 jour. Consultez la liste de contr\u00f4le de migration ci-dessus et consultez le <a href=\"https:\/\/xceed.com\/fr\/support\/\">Centre de support Xceed<\/a> en cas de probl\u00e8me.<\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph --><\/p>\n<p><mark class=\"has-inline-color has-primary-color\" style=\"background-color: rgba(0, 0, 0, 0);\"><strong>O\u00f9 puis-je trouver des exemples de code et des tutoriels de migration ?<\/strong><br \/><\/mark>R : Consultez le centre de documentation Xceed pour obtenir des guides \u00e9tape par \u00e9tape et des exemples de code concrets adapt\u00e9s \u00e0 .NET 9.<\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph --><\/p>\n<p><mark class=\"has-inline-color has-primary-color\" style=\"background-color: rgba(0, 0, 0, 0);\"><strong>Q : Quel est le principal avantage de .NET 9 pour les \u00e9quipes d&#x27;entreprise ?<\/strong><br \/><\/mark>Plateforme unifi\u00e9e, performances plus rapides et int\u00e9gration cloud facilit\u00e9e, plus une prise en charge robuste pour une UI et une gestion de fichiers s\u00e9curis\u00e9es et \u00e9volutives.<\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph --><\/p>\n<p><mark class=\"has-inline-color has-primary-color\" style=\"background-color: rgba(0, 0, 0, 0);\"><strong>Have more questions or need help upgrading?<\/strong><br \/><\/mark>Consultez notre <a href=\"https:\/\/xceed.com\/fr\/support\/\">Support Contact Page<\/a>\u2014our team is ready to help you unlock the full value of .NET 9.<\/p>\n<p><!-- \/wp:paragraph --><!-- wp:paragraph --><\/p>\n<p><!-- \/wp:paragraph --><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-294b116 e-flex e-con-boxed e-con e-parent\" data-id=\"294b116\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>","protected":false},"excerpt":{"rendered":"<p>.NET 9 est l\u00e0 \u2014 et constitue un bond majeur pour les d\u00e9veloppeurs .NET modernes. Ce guide pr\u00e9sente les fonctionnalit\u00e9s les plus percutantes, leur importance et la mani\u00e8re dont les composants Xceed vous aident \u00e0 tirer le meilleur parti de cette version.<\/p>","protected":false},"author":12,"featured_media":3189,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[141,52,50],"tags":[],"class_list":["post-3187","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-all","category-news","category-releases"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.0 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>.NET 9 Release Guide: What\u2019s New &amp; How Xceed Components Accelerate Your Apps<\/title>\n<meta name=\"description\" content=\"Explore the .NET 9 release guide for key features, performance upgrades, and best practices. Learn how Xceed components help you build faster, more secure apps.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/xceed.com\/fr\/blog\/liberations\/quoi-de-neuf-dans-net-9-guide-complet-de-la-version\/\" \/>\n<meta property=\"og:locale\" content=\"fr_CA\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\".NET 9 Release Guide: What\u2019s New &amp; How Xceed Components Accelerate Your Apps\" \/>\n<meta property=\"og:description\" content=\"Explore the .NET 9 release guide for key features, performance upgrades, and best practices. 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